Abstract: The present invention relates to an image encoding and decoding method. An image decoding method for the same may include: obtaining transform coefficients of a current block from a bitstream; determining a scanning unit and a scanning order of the current block; and rearranging the transform coefficients of the current block by scanning the same base on the determined scanning unit and scanning order.

Abstract: An image decoding method is disclosed in the present specification. An image decoding method according to the present invention may include: determining a position of a co-located block of a current block within a co-located picture (co-located picture); determining a representative motion vector of the current block by using motion information at the position of the co-located block; and deriving motion information on a sub-block included in the current block by using the representative motion vector.

Abstract: The present invention relates to an image encoding/decoding method and apparatus. An image encoding method according to the present invention may comprise generating a transform block by performing at least one of transform and quantization; grouping at least one coefficient included in the transform block into at least one coefficient group (CG); scanning at least one coefficient included in the coefficient group; and encoding the at least one coefficient.

Abstract: Disclosed herein are a video decoding method and apparatus and a video encoding method and apparatus. In video encoding and decoding, inter-prediction information for a target block may be derived, and inter prediction for a target block may be performed using the derived inter-prediction information. Combined inter-prediction information may be performed by combining multiple pieces of inter-prediction information, and the combined inter-prediction information may be added as a candidate to a list used for inter prediction. One of candidates in the list may be selected for inter prediction for the target block, and inter prediction using the selected candidate may be performed.

Abstract: An image encoding/decoding method and apparatus are provided. An image decoding method of the present invention comprises decoding first information indicating whether a maximum of N intra prediction modes are used or a maximum of M intra prediction modes are used for an intra prediction for a current block, in which the M is smaller than the N, deriving an intra prediction mode of the current block, inverse-mapping the derived intra prediction mode on a corresponding intra prediction mode among the maximum N intra prediction modes when the decoded first information indicates that the maximum M intra prediction modes are used for the intra prediction for the current block, and generating an intra prediction block by performing an intra prediction for the current block, based on the inverse-mapped intra prediction mode.

Abstract: An image encoding/decoding method and apparatus for performing intra prediction are provided. An image decoding method of the present invention comprises deriving an intra prediction mode for a current block, selecting at least one reconstructed sample line neighboring to the current block, constructing a reference sample using at least one reconstructed sample included in the at least one reconstructed sample line, and performing intra prediction for the current block based on the intra prediction mode and the reference sample.

Abstract: The present invention relates to a method for encoding/decoding a video. To this end, the method for decoding a video may include: deriving a spatial merge candidate from at least one of spatial candidate blocks of a current block, deriving a temporal merge candidate from a co-located block of the current block, and generating a prediction block of the current block based on at least one of the derived spatial merge candidate and the derived temporal merge candidate, wherein a reference picture for the temporal merge candidate is selected based on a reference picture list of a current picture including the current block and a reference picture list of a co-located picture including the co-located block.

Abstract: The present specification discloses a method of decoding an image. The method of decoding an image according to the method includes: obtaining transform skip information of a current block from a bitstream; obtaining multiple transform selection information of the current block on the basis of the transform skip information from the bitstream; and performing inverse transform on the current block on the basis of the multiple transform selection information, wherein the multiple transform selection information is used to set each of a horizontal transform type and a vertical transform type.

Abstract: Disclosed is a method of decoding an image and a method of encoding an image. The method of decoding an image includes: obtaining motion-constrained tile set information; determining, on the basis of the motion-constrained tile set information, a first boundary region of a collocated tile set within a reference picture, which corresponds to a motion-constrained tile set; padding a second boundary region corresponding to the first boundary region; and performing inter prediction on the motion-constrained tile set by using a collocated tile set that includes the padded second boundary region.

Abstract: Disclosed are a method and an apparatus for image encoding/decoding that support a plurality of layers. The method for image decoding that supports a plurality of layers includes decoding information of a first layer which a picture of a second layer including a current decoding target block refers to; mapping the information of the first layer to a picture size of the second layer, configuring a reference picture list for the picture of the second layer by adding the mapped information of the first layer and generating prediction samples of the current decoding target block by predicting the current decoding target block of the second layer based on the reference picture list, and the information of the first layer includes at least one of a sample value and motion information of the first layer picture.

Abstract: A video decoding method according to an embodiment of the present invention may include determining a type of a filter to be applied to a first-layer picture which a second-layer picture as a decoding target refers to; determining a filtering target of the first-layer picture to which the filter is applied; filtering the filtering target based on the type of the filter; and adding the filtered first-layer picture to a second-layer reference picture list. Accordingly, the video decoding method and an apparatus using the same may reduce a prediction error in an upper layer and enhance encoding efficiency.

Abstract: The present invention is about an image encoding/decoding method and apparatus. According to present invention, a method of decoding an image, the method comprising, loading information of a neighboring block of a current block; decoding a current block using the loaded information of the neighboring block; and saving information of the current block that is decoded.

Abstract: The present invention relates to a method and an apparatus for interlayer prediction, and the method for interlayer prediction, according to the present invention, comprises the steps of: deciding whether to apply an interlayer prediction to an enhancement layer; and performing a prediction on a current block of the enhancement layer based on reference information that is generalized and generated from a reference picture, which is decoded, of a reference layer, when the interlayer prediction is applied, wherein the reference layer information can be encoding information of a reference block, which corresponds to a current block of the enhancement layer, from the reference layer, and residual information.

Abstract: The present invention relates to an image encoding/decoding method and apparatus. The image decoding method according to the present invention may comprise acquiring transform coefficients distribution information of a neighboring block from a bitstream; direction-adaptively determining an intra prediction mode of a current block to be decoded, according to the transform coefficients distribution information of the neighboring block; and reconstructing the current block, based on the determined intra prediction mode, wherein the direction-adaptively determining includes determining similarity flag information corresponding to the neighboring block, based on the transform coefficients distribution information of the neighboring block.

Abstract: Disclosed herein is a method of decoding an image including determining whether a current block is in a bi-directional optical flow (BIO) mode, calculating gradient information of prediction samples of the current block when the current block is in the BIO mode, and generating a prediction block of the current block using the calculated gradient information, wherein the calculating of the gradient information of the prediction samples of the current block includes calculating the gradient information using at least one neighbor sample adjacent to the prediction samples.

Abstract: The present invention discloses an image decoding method, the method including generating a candidate list including motion information derived from a spatial neighboring block and a temporal neighboring block adjacent to a current block; deriving motion information of the current block using the candidate list; generating a prediction block of the current block using the derived motion information; and updating the derived motion information in a motion information list, wherein the generating of the candidate list is performed in such a manner as to include at least one information of the motion information included in the updated motion information list in a block decoded before the current block.

Abstract: An image encoding/decoding method may comprise deriving at least one merge candidate of a current block, generating an initial merge candidate list of the current block by using the derived at least one merge candidate and generating a reconfigured merge candidate list by using the initial merge candidate list.

Abstract: An image encoding/decoding method may comprise deriving at least one merge candidate of a current block, generating an initial merge candidate list of the current block by using the derived at least one merge candidate and generating a reconfigured merge candidate list by using the initial merge candidate list.

Abstract: The present invention relates to an image encoding/decoding method and apparatus. The image decoding method according to the present invention may comprise reconstructing an intra prediction mode of a current block, determining a reference sample for intra prediction of the current block, and generating a prediction block of the current block by performing the intra prediction on the current block on the basis of the intra prediction mode and the reference sample. The determining of the reference sample or the intra prediction may be performed on the basis of a shape of the current block.

Abstract: The present invention relates to a method and apparatus for encoding and decoding a video image based on transform. The method for decoding a video includes: determining a transform mode of a current block; inverse-transforming residual data of the current block according to the transform mode of the current block; and rearranging the inverse-transformed residual data of the current block according to the transform mode of the current block, wherein the transform mode includes at least one of SDST (Shuffling Discrete Sine Transform), SDCT (Shuffling Discrete cosine Transform), DST (Discrete Sine Transform) or DCT (Discrete Cosine Transform).